Manufacture of concrete piling



June 1965 5.1.. MYERS 3,188,817

MANUFACTURE OF CONCRETE FILING Filed April 15, 1962 2 Sheets-Sheet 1Fig. 1

L I Y )I i INVENTOR BIRDIE L. M Y E R S ATTORNEY June 15, 1965 B. L.MYERS 3,188,817

MANUFACTURE OF CONCRETE FILING Filed April 13, 1962 2 Sheets-Sheet 2INVENTOR BIRDIE L. MYERS ATTORNEY United States Patent Ofifice 3,188,817Patented June 15, 1965 MANUFACTURE OF CGNCRETE PILING Birdie L. Myers,1612 22nd St., Galveston, Tex. Filed Apr. 13, 1962, Ser. No. 187,275 1(Ilaim. (Cl. 61-5364) This invention relates to the manufacture ofconcrete piling. More specifically it relates to a unique method forproducing concrete in place. Even more particularly the method has to dowith the drilling of holes in the ground and the installation ofconcrete piling poured in place.

. In construction work where concrete piling is required or desirable,it is conventional practice to drill a hole in the ground to the properdepth with an earth auger and to then withdraw the auger whereupon thepile is formed by pouring concrete into the hole. Where the ground issoft and susceptible to cave-ins, it is common to insert a thin-walledmetal sleeve into the hole to eliminate cave-ins before and during thepouring of the concrete. In instances where the ground is swampy or verysandy and this method is not satisfactory, it is necessary to force athick walled steel vessel closed at the bottom into the ground and thenpour it full of concrete. Since concrete piles are used in manydifferent ground formations, many difficulties have been encountered inpouring piles in the first above mentioned manner. This invention isdirected toward and does solve the many undesirable aspects of theabove-mentioned methods which cause the forming of in-place concretepiles to be expensive, slow and unsatisfactory.

Various means have been devised for stabilizing soil to prevent cave-inswhen the auger is withdrawn. Treat- ,ment of the soil with stabilizingchemicals has been suggested. However, these are effective only incertain soil conditions and are expensive and time consuming.Furthermore, the important problem of concrete set-up is aggravatedwhenever time is lost, and in any method for that matter, since it isgenerally impossible to mix the concrete on the job-site.

Another problem encountered in the production of inplace concrete pilingis segregation of the concrete as it is poured into the hole. From anyheight above about three feet, concrete will segregate unless theconsistency is thick, and the proper strength is unattainable in thatcase as well as reducing the limited time before set-up. In most casesit is almost impossible anyway to keep the proper mixture fromsetting-up before being poured into the hole and various retardants usedalways interfere with the strength.

It is, therefore,the object of this invention to manufacture concretepiling in-place. It is a further object to manufacture concrete pilingin-place so as to avoid hole cave-ins. It is also an object tomanufacture concrete piling in-place wherein the concrete does notsegregate when poured and yet maintains maximum strength. It is finallyanother object of this invention to manufacture in-place concrete pilingwhich does not set up prematurely before or during the pouring and yetmaintains maximum strength. These and other objects of the inventionwill be apparent to those skilled in the art by the followingdescription.

According to this invention, concrete pilings are manufactured in-placeby the combination of steps which consist of drilling a hole in theground with a tubular auger open at its lower end and provided with abit having replaceable angled teeth and an opening in the bit for thepassing of fluid, forcing the excavated material upward out of the holewith the special flights of the auger, injecting retarded concretethrough the tubular auger into the hole after the bit has drilled to thedesired depth, and then simultaneously withdrawing the bit and the augeras the said concrete is pumped into the hole thus filling the hole withnon-segregated concrete of the proper strength and consistency whichwill not set-up because of a unique retardant mixed therein.

In practicing this method, the earth auger is not removed when thedrilling is completed and thus the auger forms at all times the wallreinforcing means for that portion of the hole not yet filled withconcrete. The concept of slowly withdrawing the auger as the concrete ispoured eliminates the need for extra equipment and also reduces thenumber of steps to be performed in forcing concrete piles into theground and, therefore, represents a substantial saving in labor, time,and materials while still providing additional strength and efficiencyto the finished pile.

The accompanying drawings will illustrate the process but are not to beconstrued as limiting it.

FIGURE 1 is a view of the drilling apparatus and equipment used tooperate the drilling apparatus.

FIGURE 2 is a view of the auger and bit used to drill the earth holes.

FIGURE 3 is a view of the unique bit designed to be used in the practiceof this method of drilling holes for concrete piling.

In FIGURE 1, the equipment may include a drilling frame 1 which isattached to and supported by the bed of a truck, tractor or other mobileequipment 2. The tubular auger 3 is shown inside the drilling frame 1and is complete with flights and attached to the headgear 5 which servesto force the auger into the ground by its weight and also contains thehydraulic drive mechanism to turn the auger. The hydraulic fluid pump tothe drive mechanism is located on the bed of the mobile vehicle 2. Thehead gear is raised by a cable apparatus 9 which is attached to andoperated by a drive on the vehicle 2. The bit 4 is shown after a hole 10has been drilled and just prior to the concrete being pumped through theauger and bit into the hole. After removing the auger and bit as thehole is filled with concrete 11, the completed concrete piling is shownas 20. The concrete is pumped by means of an air driven pump 7, throughhose 6, into the auger 3 and thence into the hole. The vibrator chain 8acts to densify the concrete as it passes through the auger andeliminates any entrained air pumped with the concrete. In addition tolling all voids in the flowing concrete by its vibrating action,vibrator chain 8 also acts to keep the concrete from separating intosolid and liquid phases as it flows the length of the auger. This isaccomplished by fastening the chain to head gear 5 and allowing it tohang free the length of the auger. The vibrator chain turns and.vibrates with the turning action of the head gear and thereby acts tofill concrete voids and maintain the concrete in a non-segregatedcondition.

FIGURE 2 simply shows in more detail the construction of the tubularauger 12 and the flights 13. The bit 14 is attached to the bottom of theauger so that the flights of the bit line-up with the flights of theauger. The bit is constructed so that the bit teeth 15 are set in tworows each at approximately 45 with the other so that the drilling isperformed in a manner which will push the earth outward and then flowevenly upward to the auger flights.

In FIGURE 3 the bit 116 is shown in even more detail with the bitspirals 17 indicated. The angle of the two rows of teeth 18 can be seenand the hole 1-9 from whence the concrete flows can be easilyidentified.

When it is desired to manufacture in-place concrete piling in accordancewith this method and with this apparatus, the mobile vehicle is merelymoved to the desired location and the drilling frame erected in theproper manner. The auger is then rotated by the hydraulic drivemechanism and the hole is drilled by the bit to the proper Idepth.Normally the approximately '30 foot anger is satisfactory for most holesbut in swampy and sandy areas and Where large industrial towers or heavyvibrating equipment are to be installed, holes up to 100 feet may berequired. In that case, 2 or 3 orpossibly 4 sections of the tubularauger will be required. This is handled in the same manner as oil fielddrilling wherein 1 .t-he head gear is disconnected from the auger andraised to the top of the frame. Another section of tubular anger isswung into place, attached and the'dril ling continnes. When the hole isdrilled to the proper depth, the rotation is stopped and the airoperated, concrete pump is started. All during this period and While thehole is filled with concrete, the auger acts as a wall support forthehole to'prevent cave-ins 'andunder all but extreme conditions is,adequate. The concrete is, then pumped in and the auger and bit arewithdrawn from the hole as it fills but at a rate sothat theconcreteldoes not fall any further than about one foot andpreferably'the tip of the bit is in the concrete at, all times.

, The size of the holes which. may be drilled and'concrete'pilingsinstalled therein -;by.this method varyfrom aboutsix inches in diameterto as high as thirty six inches in diameter although preferably themosttpractical and most economic size is from about 8 inches indiameter.

7 inches to about '14 Perhaps the most important factor in this methoddrf manufacturingin-place concrete piling is' the compositionpf theconcrete, The particular advantage .of con-' .crete piling isthesuperior strength and non-corrosive surface it possesses overconventional materials such as .wood and steel. 'However, underdiffering conditions concrete loses its strengthiand does not properlyper- :forrnits intended task. Some of these conditions are segregating,excessive. or insufficient water, and premature hardening.

, segregating is when mostof the aggregate falls to the bottom of thehole and ,the top 'portion'consequently has inferior strength. This can.be caused by allowing the concrete to free-fall too far .or by usingtoo" much water. Theme of excessive or insuflicie'nt-water createsseparate problems allin themselves. Excessive water causessegregationgas noted-aboveand results .in low. strength. Too much watermaybe used,1when' pumping conditions are severe or when prematurehardening is imminent. .Insuffi cient Water is a common mistake inpoured concrete since of concrete. of thefollowing composition:

stronger than ordinary concrete of the same proportions of cement, sandand water and is, therefore, -a necessary part of the superior concretepiling manufactured by this method. I

The following example is illustrative of the concrete composition of.this invention but should not be construed as limiting it in any manner.

Example I Three concrete cylinders six inches in diameter andtwelveinches long were cured, capped and broken in accordance withstandard AmericanStandard Testing of .Materials Methods andSpecifications. Two beams four inches by four inches by eighteen incheswere cured and broken in accordance with standard ASTM specifications.All of these cylinders and beams were constructed 7 Lbs. TrinityPortland cement 1,128 No. 16-Co1oradosand a 2,630 Symentard 12 Water 520The results showed-that 28 day strength on the cylinders gave averagebreak load of 102,000 lbs. and 7 day'strength gave abreak load of45,000lbs. The rupture modules on the. beams averaged 700.; It isapparent that these [results show approximately 10%, greater strengththan the best concreteused in bridge construction. What is claimed is: V

In a method for manufacturing concrete piling inplace by drilling a:hole in the ground with a tubular auger having-flights to removetheearth and thereafter filling the hole'with concrete'passing throughsaidtubular auger as said auger -is removed from said hole, the

improvement which consists ofdrilling said hole with a :tubular augerhaving a bit on its lower end with at least 7 two rows of multiple teethset at about a 45 angle with the vertical =to drilla holeat least aslarge as the diameterof said auger, said bit having anopening into saidtubular auger-and flights .to' direct drilled material away fromsaidopening and 'ontoiflights on said auger, and

1 thereafter forming said. concrete pilingin place'by air thiseliminates segregation but it results in low strength concrete andpremature hardening. The separate problem of premature set-up is themost severe in the manufacture of in-place concrete piling. When aconcrete truck must travel long distances toan industrial job site,premature hardening nearly always occurs to some extent. It again .isaggravated because the concrete must then be pumped through apump,-hose,and tubular auger.

All of the above mentioned problems can be elimi-' nated by using aunique retarding densifieri Besides retarding the hardening .of concreteit acts as a densifier vto form alstronger concrete. The specificmaterial used in this method is a compound known to the trade asSymentard, a chemical compound manufactured by the A. .C. Horn Company.This compound is constituted of.

minor proportions, that is, less than 5% 'by Weight each of nitrogen,sulfur, lignin, sulfonic acid, and major pro portions that is, at least10% by weight. each with the total being greater than 60% by Weight ofcarbon, glucase, hydrogen and silica. The resulting concrete is pumpingthrough said auger into said' hole concrete containing therein from:0.1% to 1.0% by weight of the 'concrete of a retarding densifiercontaining major proportions ofcarbon, hydrogen, glucose and silica andminor proportions' of nitrogen, sulfur, 'lignin and sulfonic 'acid,-.said*pumping'of said concrete through said auger being carried out by'pouringsaid concrete over arotating and vibrating chain suspendedinside the entire length of; said auger, said vibrations being causedby'the withdrawalof said auger-fromsaid hole.

References Cited by the Examiner EARL J. wrrMER, Primary Examiner. JACOBSHAPIRO, Examiner.

